Version: V3

# IUniswapV3PoolDerivedState

Contains view functions to provide information about the pool that is computed rather than stored on the blockchain. The functions here may have variable gas costs.

## Functions​

### observe​

  function observe(    uint32[] secondsAgos  ) external view returns (int56[] tickCumulatives, uint160[] secondsPerLiquidityCumulativeX128s)

Returns the cumulative tick and liquidity as of each timestamp secondsAgo from the current block timestamp

To get a time weighted average tick or liquidity-in-range, you must call this with two values, one representing the beginning of the period and another for the end of the period. E.g., to get the last hour time-weighted average tick, you must call it with secondsAgos = [3600, 0]. The time weighted average tick represents the geometric time weighted average price of the pool, in log base sqrt(1.0001) of token1 / token0. The TickMath library can be used to go from a tick value to a ratio.

#### Parameters:​

NameTypeDescription
secondsAgosuint32[]From how long ago each cumulative tick and liquidity value should be returned

#### Return Values:​

NameTypeDescription
tickCumulativesint56[]Cumulative tick values as of each secondsAgos from the current block timestamp
secondsPerLiquidityCumulativeX128suint160[]Cumulative seconds per liquidity-in-range value as of each secondsAgos from the current block

timestamp

### snapshotCumulativesInside​

  function snapshotCumulativesInside(    int24 tickLower,    int24 tickUpper  ) external returns (int56 tickCumulativeInside, uint160 secondsPerLiquidityInsideX128, uint32 secondsInside)

Returns a snapshot of the tick cumulative, seconds per liquidity and seconds inside a tick range

Snapshots must only be compared to other snapshots, taken over a period for which a position existed. I.e., snapshots cannot be compared if a position is not held for the entire period between when the first snapshot is taken and the second snapshot is taken.

#### Parameters:​

NameTypeDescription
tickLowerint24The lower tick of the range
tickUpperint24The upper tick of the range

#### Return Values:​

NameTypeDescription
tickCumulativeInsideint56The snapshot of the tick accumulator for the range
secondsPerLiquidityInsideX128uint160The snapshot of seconds per liquidity for the range
secondsInsideuint32The snapshot of seconds per liquidity for the range